2 stroke gearbox oil compatibility

[Abax25]

I have three children who all race dirtbikes. All of them are on 2 strokes. I’m changing a ton of gearbox oil throughout the year.

While at my local auto zone this morning, they had Pennzoil ® ATV/UTV Premium Plus Engine Oil on clearance for $3 a quart.

it’s wet clutch safe. Any reason I shouldn’t stock up on this, and save some money?

 

[JavierH19]

Good stuff i'd use it no doubt if I could get it for that.

 

[IndyIan]

I imagine it will work just fine. I'm in the "change the cheaper oil more often" camp for dirt bikes.

 

[Speedbird001]

I would speculate anything wet clutch safe is fine. It was ages ago [but has 2T changed that much?] We were told by the Honda and independent shop and manual simply: "Change after every race"

Fuel dilution is certainly the killer of 2T crankcase oil, but were talking less than s qt per drain and fill right?

 

[Abax25]

I would speculate anything wet clutch safe is fine. It was ages ago [but has 2T changed that much?] We were told by the Honda and independent shop and manual simply: "Change after every race"

Fuel dilution is certainly the killer of 2T crankcase oil, but were talking less than s qt per drain and fill right?

There is no fuel dilution on a 2t….

I have to change the gearbox oil every race. Shifting quality is out the window at the end of each race regardless of what fluid I’ve tried over the years.

 

[IndyIan]

There is no fuel dilution on a 2t….

I have to change the gearbox oil every race. Shifting quality is out the window at the end of each race regardless of what fluid I’ve tried over the years.

Wow, do they use lots of clutch slipping? I guess that could dump a ton of heat into the oil. How often do you change the clutch?
I'm closer to every 10hrs on the YZ250, but we aren't racing and don't slip the clutch much on it at all, just the odd tight corner in 2nd, and aren't really riding it hard enough get a large amount of heat into the gearbox.
I can't really tell any difference other than a touch more clutch drag with fresh oil in?

 

[burbguy82]

I have three children who all race dirtbikes. All of them are on 2 strokes. I’m changing a ton of gearbox oil throughout the year.

While at my local auto zone this morning, they had Pennzoil ® ATV/UTV Premium Plus Engine Oil on clearance for $3 a quart.

it’s wet clutch safe. Any reason I shouldn’t stock up on this, and save some money?

That is a great deal. I would buy all they had
Does the engine and gearbox use a shared sump? If so, I would use that all day. especially for the price.

 

[cpayne5]

Being wet clutch safe, I'm sure it's a fine oil. Stock up!

What bikes do you have? What kind of racing?

I switched to ATF Type F in my son's two KX85s last year. He races hare scrambles and it seems to be working great. One of the things I was looking for in an oil was lower viscosity to help with the dead engine starts of this type of racing.

 

[cpayne5]

That is a great deal. I would buy all they had
Does the engine and gearbox use a shared sump? If so, I would use that all day. especially for the price.

On two stroke dirt bikes, the top end and crankcase is lubricated by the gas/oil mix while the clutch and transmission share a different oil. OP Is talking about the clutch/gearbox oil here.

 

[burbguy82]

On two stroke dirt bikes, the top end and crankcase is lubricated by the gas/oil mix while the clutch and transmission share a different oil. OP Is talking about the clutch/gearbox oil here.

Well then, I would not strive to use engine oil for this gearbox, unless it was the correct oil.

 

[IndyIan]

Being wet clutch safe, I'm sure it's a fine oil. Stock up!

What bikes do you have? What kind of racing?

I switched to ATF Type F in my son's two KX85s last year. He races hare scrambles and it seems to be working great. One of the things I was looking for in an oil was lower viscosity to help with the dead engine starts of this type of racing.

30 years ago, that's what I ran in my old dirt bike, a IT200, and for a whole season! We did lots of road running, but still probably over 100hrs per year. It would come out looking used, but not terrible. But again, that bike didn't need much clutch slipping, and I always used the clutch to shift, so it wasn't full on "red mist" racing usage.

 

[Abax25]

Well then, I would not strive to use engine oil for this gearbox, unless it was the correct oil.

It’s wet clutch safe. Aka for a 4 stroke shared sump. Which is fine for a 2t gearbox. Only made this post, because I wasn’t sure if this being for an ATV somehow has something in it that would cause issues.

On 2t you generally either use motorcycle engine oil or dedicated transmission lube. I’ve found motorcycle oils hold shifting quality longer than the manual transmissionmission based fluids anyways.

 

[IndyIan]

Well then, I would not strive to use engine oil for this gearbox, unless it was the correct oil.

Almost all 4 stroke motorcycles and dirt bikes have a shared sump for engine and gearbox, so 4T motorcycle oil works well in 2t gearbox's too.
I think that a specific fluid just for 2T gear boxes could be "better", but clearly 4t motorcycle oil works well enough in dirtbike transmissions.
I still find it amazing that 1quart of oil keeps a 450cc 55hp, or 250cc 13k rpm 45hp, dirt bike engine and transmission alive even for 5hrs!

 

[Abax25]

Being wet clutch safe, I'm sure it's a fine oil. Stock up!

What bikes do you have? What kind of racing?

I switched to ATF Type F in my son's two KX85s last year. He races hare scrambles and it seems to be working great. One of the things I was looking for in an oil was lower viscosity to help with the dead engine starts of this type of racing.

I’ve never tried type f but know a lot of people seem to have great success.

Hare scrambles as well, and the occasional hard enduro race.

My eldest refuses to move away from the YZ250 platform. It has electric start, but it can be problematic to say the least.

The other two bikes are shercos. A 250 and 125. Which have been a joy to own. The kid are in love, and we haven’t had any issues.

 

[cpayne5]

I’ve never tried type f but know a lot of people seem to have great success.

Hare scrambles as well, and the occasional hard enduro race.

My eldest refuses to move away from the YZ250 platform. It has electric start, but it can be problematic to say the least.

The other two bikes are shercos. A 250 and 125. Which have been a joy to own. The kid are in love, and we haven’t had any issues.

Gotcha. Yeah, the YZ250 is a great bike, but electric start sure does make things easier at times (off camber/hill situations).

We have a few people in our series who run Shercos. One Sherco family built a YZ85 into a "Sherco" for their youngest son. It even has a headlight and electric start. He had a 65 "Sherco" before that, too.

My son will be moving to KX112s either next year or the year after.

 

[Abax25]

Gotcha. Yeah, the YZ250 is a great bike, but electric start sure does make things easier at times (off camber/hill situations).

We have a few people in our series who run Shercos. One Sherco family built a YZ85 into a "Sherco" for their youngest son. It even has a headlight and electric start. He had a 65 "Sherco" before that, too.

My son will be moving to KX112s either next year or the year after.

View attachment 339274

That’s awesome! They grow up so fast.

I’m old and washed up and can’t keep up with any of my kids at this stage. It’s still a joy watching them enjoy the sport so much. It’s been really good for each of them. They are super strict about what they eat, working out, and know the moment they slip with school the bikes are parked. I’ve never had to test that thankfully!

 

[Japanese]

It’s wet clutch safe. Aka for a 4 stroke shared sump. Which is fine for a 2t gearbox. Only made this post, because I wasn’t sure if this being for an ATV somehow has something in it that would cause issues.

On 2t you generally either use motorcycle engine oil or dedicated transmission lube. I’ve found motorcycle oils hold shifting quality longer than the manual transmission based fluids anyways.

That's the right oil for your 2-stroke bikes, regardless that ATV/UTV is mentioned. It's the right viscosity and is made for wet clutches.
Pennzoil ATV/UTV Premium Plus 10W-40

Valvoline also has two different 10W-40 oils - one for motorcycles and one for ATV/UTV. The difference is that the ATV oil has a bit lower amounts of zinc and phosphorous, and a bit lower TBN vs the dedicated motorcycle oil. The additive package is a bit different but not a lot.

Valvoline 10W-40 motorcycles
https://sharena21.springcm.com/Public/Document/18452/c7c5417a-e481-e711-9c10-ac162d889bd3/4707a799-e29c-e711-9c10-ac162d889bd3

Valvoline 10W-40 ATV/UTV
https://sharena21.springcm.com/Public/Document/18452/83150d20-e481-e711-9c10-ac162d889bd3/3b07a799-e29c-e711-9c10-ac162d889bd3

Don't put manual transmission fluid in those engine. Those are lower viscosity (about SAE 30 or lower) than you need. If you want something different and cheaper than 10W-40 motorcycle oil you can try SAE 80 or 75W-90 or SAE 90 gear oils. Those are equivalent to the 10W-40 motor oil viscosity. But also they may have friction modifiers and then your clutches will start to slip.

 

[Japanese]

I switched to ATF Type F in my son's two KX85s last year. He races hare scrambles and it seems to be working great. One of the things I was looking for in an oil was lower viscosity to help with the dead engine starts of this type of racing.

Interesting decision.
How many miles or hours total do you have on that oil in that engine?

 

[ZeeOSix]

I have three children who all race dirtbikes. All of them are on 2 strokes. I’m changing a ton of gearbox oil throughout the year.

What do the owner's manuals call out for viscosity?

 

[cpayne5]

Interesting decision.
How many miles or hours total do you have on that oil in that engine?

Type F has been used in 2T bikes for a long time.

70+ hours over the past year on each bike. 15+ races. I pulled the clutch pack on one of them a few weeks ago and everything is still within spec after 100+ hours (factory parts).

I've used Supertech and Providence (Rural King) Type F over that time.